1. Field of the Invention
The present invention relates to a mixing unit for mixing a fluid such as a liquid or a gas and a device using such a mixing unit, and, more particularly, relates to a mixing unit that can be suitably utilized for static mixing where a fluid is mixed by being passed, dynamic mixing where a fluid is mixed by rotation within the fluid, and to a device and a method using such a mixing unit.
2. Description of the Related Art
As a static mixing device for mixing a fluid, a Kenics-type static mixer or the like is widely used. Since this type of static mixing device generally does not include a movable component, the static mixing device is widely used in fields, such as the chemical industry and the food industry, in which fluids are required to be mixed in piping. On the other hand, as a dynamic mixing device, a product is widely used in which an agitation impeller is provided in a fluid within an agitation vessel and which rotates the agitation impeller to mix the fluid.
As a conventional static fluid mixing device, there is a static fluid mixing device which includes a tubular case body and a plurality of types of disc-shaped elements where a plurality of holes are drilled a predetermined space apart within the tubular case body, and in which the elements are sequentially combined in the direction of thickness thereof, are fitted and are fixed with connection hardware.
In the fluid mixing device described above, a plurality of types of elements are sequentially combined, and thus static mixing agitation caused by the division and combination of a fluid is performed, and mixing agitation is also performed such as by eddies and disturbance resulting from enlarged and reduced cross sections and shearing stress.
However, in the fluid mixing device described above, since the direction from the inlet to the outlet of the mixing device is the same as the direction of the division and aggregation of the fluid, its static mixing effect is low. Although the cross sections of holes are enlarged and reduced to increase its flow resistance and thus the mixing effect is improved, the loss of pressure in the entire device is increased. Since the holes are trapezoidal and have a flow reduction portion, it is difficult to process the holes.
As a conventional agitation device for dynamic mixing, there is an agitation device in which a propeller-like agitation blade provided on a rotation shaft and a plate-like auxiliary blade provided below the agitation blade. In the conventional agitation device, if only one auxiliary blade is provided, or in the case where a plurality of auxiliary blades are provided, at least one auxiliary blade is disposed so that the center angle is shifted from the equiangular position, or is formed in a shorter than the other auxiliary blade, whereby a low speed region formed at a bottom of an agitation vessel is not staid in the same region and the adhesion of an object to be agitated to the bottom part of the agitation vessel is suppressed.
According to the conventional agitation device, however, although the position of the low speed region at the bottom of the agitation vessel can be displaced from the center by the auxiliary blade and particles are liable to accumulate in the low speed region, the propeller-like agitation blade or the plate-like auxiliary blade roles up the particles accumulated in the low-speed region in the liquid and has been difficult to highly mix the fluid.
As a conventional adhesive dispensing unit for mixing fluids and dispensing the mixed fluid, there is a dispensing unit having a storage container for storing a main agent and a curing agent of a two-component curing type adhesive, a nozzle in which mixing blades are disposed, an extruder for extruding the main agent and the curing agent from the storage container to the nozzle, and an operating lever for driving the extruder. When an operator operates the operating lever, the main agent and the curing agent pass through the mixing blades in the nozzle from the storage container to be mixed, and are dispensed from a tip portion of the nozzle.
In the conventional adhesive dispensing unit, the mixing blades are formed such that spirally twisted blades are continuously formed while changing the twist direction of the blades. The mixing blades mix a liquid (fluid) such as a main agent and a curing agent by spirally flowing the liquid. In the case of the two-component curing type adhesive, even if the main agent and the curing agent are mixed at a predetermined ratio, if the mixing is insufficient, appropriate adhesive strength may not be obtained in some cases. Therefore, it is necessary to form the mixing blades long in order to sufficiently mix the liquid, and the nozzles in which the long mixing blades are arranged are also necessary to be long. If the nozzle becomes long, it becomes difficult to position the nozzle with respect to the object to be ejected and to operate making coating. In addition, the amount of fluid remaining in the nozzle to be discarded after application and use is liable to be large, which wastefully consumes the fluid. Further, due to the long nozzle, the total length of the adhesive dispensing unit also becomes long, and also handling of the adhesive dispensing unit is inconvenient.